The invention relates to a method, a system, an image generation device and a control device for documenting the condition of a motor vehicle and to a correspondingly equipped motor vehicle.
DE 10 2005 058 353 A1 discloses an apparatus with which the condition of a motor vehicle can be documented. Said apparatus has a turntable, on which the motor vehicle must be arranged. A digital video camera is used to take recordings of the motor vehicle while it is rotated on the turntable. In the process, all the individual recordings and additional data sets that are created for a certain vehicle can be assigned to each other by identification information. The apparatus can be connected to a data network, and the image recording can also be carried out in a remote-controlled manner. Such an apparatus allows the condition of a motor vehicle to be captured in a very precise manner.
However, this known apparatus is very complex and expensive. It is essential for vehicle hire companies that the motor vehicles can be returned at many different locations. If it were desired to use this known apparatus to document a motor vehicle, a recording station of this type with a turntable would have to be installed at every return location, which is not economically feasible.
Car-sharing companies are companies that manage the organized, collective use of one or more motor vehicles. Car-sharing companies of this type are often not-for-profit organizations with a low budget. It is fundamentally not possible for such organizations to provide such a complex station with a turntable.
However, it would be very advantageous for vehicle hire and car-sharing companies if the condition of the motor vehicles operated by the respective companies could be documented regularly.
German patent publication no. DE 10 2013 211 005 A1 discloses a method for transmitting a current condition of a motor vehicle, in which a conventional digital camera is used as the image-capturing device. Preferably, a digital camera provided in a mobile telephone (smartphone) is used. The images captured with the digital camera are transmitted to a computation device on which reference images are provided. The computation device uses the transmitted images to check the current condition of the exterior of the motor vehicle by comparing the transmitted images with the stored reference images. If a digital camera integrated in a smartphone is used, a software module (application) can be executed on the smartphone, which software module gives the user of the smartphone instructions about the position from which and the direction in which said user should photograph the motor vehicle. Such instructions can be displayed by means of arrows on a screen provided on the smartphone.
A method of this type for capturing the condition of a motor vehicle can be carried out cost-effectively at different locations. The investment costs are very low. Nevertheless, damage to the motor vehicle can be clearly ascertained or a damage-free condition of the motor vehicle can also be clearly captured.
The invention is based on the object of developing a method and a system for documenting the condition of a motor vehicle such that the images captured thereby can be used as reliable evidence.
In the method according to the invention for documenting the condition of a motor vehicle with an image generation device, which is coupled to a control device of the motor vehicle by a data link, an image generation signal is initiated, which is present both at the control device of the motor vehicle and at the image generation device. The image generation signal triggers the capturing of an image of a motor vehicle with the image generation device. Furthermore, the image generation signal triggers the generation of a data stamp by the control device of the motor vehicle. The data stamp is linked to the image.
Since the data stamp is generated by the control device of the motor vehicle, it is created independently of the image generation device. The data stamp thus originates from the motor vehicle itself. Images having such a data stamp thus have substantially greater cogency than images without such a data stamp, since said images can only be created with the respective vehicle to be documented.
The data stamp preferably comprises one or more of the following information items:
a time information item that describes the time at which the image was generated,
a location information item that describes the location of the motor vehicle during image generation,
an information item relating to vehicle-specific parameters, e.g. mileage of the vehicle, vehicle identifier, predefined operating parameters, vehicle registration plate, chassis number,
an information item relating to environmental parameters, e.g. temperature, precipitation information, wind speed,
camera parameters, such as image resolution of the camera, zoom setting (focal distance), use of flash, location and/or orientation of the camera,
a driver information item that describes the last or next-to-last driver and front passenger of the motor vehicle.
The vehicle-specific parameters are used on the one hand to document the driving condition of the vehicle and can be used on the other hand to determine an unambiguous identification of the vehicle. A multiplicity of different vehicle-specific parameters represents a form of fingerprint for the vehicle, which also allows an unambiguous identification of the vehicle at a later point in time.
The image and the data stamp linked with the image form a data unit, which is also referred to below as a stamped image. The stamped image is preferably signed digitally. The digital signature is preferably carried out with an asymmetric, cryptographic method, so that the signature cannot be removed from the stamped image subsequently, and it can also be clearly ascertained from the signature that the data stamp originates from a certain motor vehicle. The stamped image can thereby be assigned unambiguously to a vehicle at any time subsequently.
The image generation signal is preferably initiated by the control device of the motor vehicle. The image generation is thereby controlled exclusively by the control device of the motor vehicle, creating a further security barrier to prevent improperly generated images being used to document the condition of the motor vehicle.
The image generation device can be authenticated with respect to the control device of the motor vehicle. Preferably, an identifier of the image generation device is linked to the respective image. It is also possible for only certain image generation devices to be authorized by the control device to capture the images of the motor vehicle.
Environmental information about the motor vehicle can be captured using sensors, which are provided on the motor vehicle, and linked to the respective image. Such environmental information is e.g. weather data (temperature, precipitation) and/or images of the environment of the motor vehicle, which are captured using cameras arranged on the motor vehicle. Preferably, at the same time as the generation of the image of the image generation device, an image of the environment of the motor vehicle is also captured by a camera arranged on the motor vehicle, the viewing direction of which points in the direction of the image generation device, so it is clearly documented that the image generation device was in the vicinity of the motor vehicle and the viewing direction thereof was pointing at the motor vehicle. This allows a subsequent check as to whether a certain image of the motor vehicle was actually recorded by the image generation device. The environmental information can alternatively also be read out of a database. This is expedient particularly if the motor vehicle is connected to the Internet. The environmental information read out of a database can also be used in addition to the environmental information determined by sensors.
Preferably, route coordinates of the motor vehicle of a route covered immediately leading up to a certain event are linked to the image. The certain event can be the generation of an image of the motor vehicle and/or the ascertainment of an accident. Accidents are detected e.g. with acceleration sensors or impact sound sensors, which are used to set off airbags. The route coordinates can comprise the location coordinates of the motor vehicle along the route covered. The route coordinates can also comprise a combination of location and time coordinates of the route covered. Preferably, the resolution of the route coordinates is more precise, the closer the route is in time and space terms to the certain event.
Such capturing of the route coordinates of the motor vehicle before a certain event allows subsequent provision of unambiguous evidence for an accident, since the route information of the motor vehicle is available. In conjunction with documentation of the condition of the motor vehicle, an expert can subsequently reconstruct an accident process very precisely.
The captured image can also be compared with a reference image in order to ascertain changes and in particular damage to the motor vehicle automatically. Such a comparison with a reference image is known from German patent publication no. DE 10 2013 211 005 A1, for which reason reference is made to said document in full.
The invention also relates to a system for documenting the condition of a motor vehicle with an image generation device, which is coupled to a control device of the motor vehicle by a data link, the image generation device being configured such that, triggered by an image generation signal, an image of the motor vehicle is created with the image generation device, and the control device of the motor vehicle being configured such that, triggered by the image generation signal, a data stamp is generated by the control device, the data stamp being linked to the image.
The image generation signal can be initiated by a user of the image generation device. However, it can also be initiated by the control device of the motor vehicle.
The data link between the image generation device and the control device of the motor vehicle is preferably configured to carry out real-time communication, so the image generation signal is present at the image generation device and the control device of the motor vehicle almost simultaneously.
The data link is preferably a W-LAN data link. However, it can also be another radio data link, such as a Bluetooth data link. In principle, it is also possible to use the Internet as the data link, although real-time communication is generally not possible using the Internet. If the Internet is used as the data link, it is expedient to provide each individual item of data generated or captured with a time stamp both in the image generation device and in the control device, so that the exact sequence of the data generation or data capture can be ascertained subsequently. Another wireless or wired data link can also be used instead of a radio data link.
The resolution of the image to be transmitted or the size of the data stamp to be transmitted can be adjusted depending on the available bandwidth. If the captured images are transmitted to the control device of the motor vehicle and the bandwidth is low, it is possible for only one image with low resolution to be transmitted. On the other hand, if the data stamp that is generated by the control device of the motor vehicle is transmitted to the image generation device in order to be linked to the image there, the amount of data can be limited accordingly and, for example, only a time stamp can be transmitted.
The image generation device can be a digital camera. It can be a camera for still images or individual images or else for video recordings. The image generation device preferably has an interface to a radio data link. The image generation device can be a digital camera for generating two-dimensional images. However, it can also be a camera for generating three-dimensional images, e.g. a stereo camera or a time-of-flight camera.
If a camera for generating three-dimensional images is used, deformations in the vehicle can be clearly documented. This is advantageous particularly if an automatic comparison with a reference image takes place.
The image generation device can also be part of a mobile terminal, such as a smartphone, tablet, smartglasses etc.
The image generation device preferably has a zoom lens and/or a flash device.
Within the scope of the invention, an image generation device for documenting the condition of a motor vehicle can also be specified, which device can be coupled to a control device of the motor vehicle by a data link. The image generation device is configured such that, triggered by an image generation signal, it creates an image of the motor vehicle and outputs data of the image to the motor vehicle in order to link a data stamp created in the motor vehicle by the image generation signal.
Within the scope of the invention, a control device for a motor vehicle can also be specified, which device is configured such that it can be coupled to an image generation device by a data link. Triggered by an image generation signal, by which the image generation device creates an image of the motor vehicle, the control device generates a data stamp for linking the data stamp to the image.
Within the scope of the invention, a motor vehicle can also be specified, which comprises a corresponding control device.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.